An increase in supply is always a good thing. However, the issue is how quickly players can dump loot (demand). Build times protect us all from players dumping 100% of their loot all the time. However, walls have no build time, and virtually limitless demand (few players max them). Thus, most loot can still be dumped out on walls. You are not going to see awesome storage raids often until players have an incentive to hold larger amounts of loot. The only current incentive is to afford expensive upgrades, which don't come around very often. Other than that holding loot is essentially punished.
So you have a system designed around attacking active players along with an incentive/disincentive desgined to punish harshly those holding lots of loot. Brilliant. Personally I see no reason why the loot player A holds should have much impact on the reward player B gets for attacking A. But I don't run the zoo.

